Hood-lifter mechanism



Sept. 5, 1950 Filed Feb. 18, 1947 E. E. FOSTER 2,520,921

HOOD-LIFTER MECHANISM 2 Sheets-Sheet 1 awe/MM EoZwL n E. Fas r Sept. 5, 1950 E. E. FOSTER 2,520,921

HOOD-LIFTER MECHANISM Filed Feb. 18, 1947 2 Sheets-Shed 2 W IIQRRETT:

2] W0 onion Patented Sept. 5, 1950 UNITED STATES PATENT OFFICE HOOD-LIFTER MECHANISM Edwin E. Foster, Austin, Tex. Application February 18, 1947;,SerialNo. 729,379

7 Claims. 1

This invention .relates to a hood or cover lifter particularly for the hoods and trunk compartments of automobiles and thelike.

The object of the invention is to provide a counterweighting mechanism for hoods, covers and tops which perfectly balances the hood through its entire stroke, and also automatically applies a hold-down force when the hood is completely closed or down. Another object of the invention resides in the mounting of a counterweight spring which in one position will hold the hood down and in another position will act to counterweight the hood.

A further object of the invention is to provide a counterweighting mechanism which provides an extra strong lift at the start of the up-str'oke of the hood at which time the hood is apt to be stuck down due to rubber bumpers and the like. A still further object resides in a special type of spring which is pre-tensioned and which maintains its force except for the force which is required to counterweight the hood through distance.

Further objects Will be apparent from the following description when considered in connection with the accompanying drawings in which:

Figure 11s a side elevation partly in section of the mechanism applied to a hood with the parts in the up or open position,

Fig. 2 is a view similar to Fig. 1 showing the spring ID at the end H.

parts in the down or closed position and unlatched, I

Fig. 3 is a side elevation partly in section of the mechanism and the entire length of hood with the parts in the down or closed position and latched,

Fig. 4 is a top plan view partly in section of the mechanism and in the position of Fig. 3,

Fig. 5 is an end view of a number of details, and

Fig. 6 is a plan view of a special link.

The mechanism according to this invention may be applied to any type of cover, hood or top, such as a phonograph lid ortop, photograph enlarging machines, etc. but for purpose of illustration the device is shown on the drawing :asapplied to a hood of an automobile;

The hood or cover I is suitably secured on a frame member 2 havin aninverted U-shaped bracket or end portion M and thisframe is supported by means of links 5 and 6 to a stationary bracket 3 removably attached to the cowl 4 of the automobile. The two connecting links '5 and 6 are pivoted to thebracket 3 and the movable frame 2 to form a well known four-bar linkage I stroke.

hinge, which will permitthe hood to be raised and 'loweredwith'out any difficulty. The special link 1, shown in detail in Fig. 6, is pivoted to the U-shaped bracket 14 by means of pins 8 and 9 and the narrow end of the link I is pivoted to a The other end of the spring in is pivoted to the bracket at [2 and the spring is shown in its normal position in'Fig. 1. This spring 10 consists of a coiled tension spring which has a considerable amount of pretension built into it and each end of the spring is provided with a short lever-arm leg 15 extending at an angle relative to the longitudinal axis of the coiled portion and terminates in an eye portion as shown in Fig. 1. The leg members [5 are in the same plane with the center axis of the coil.

A cord or cable 13 leads to the dash of an automobile and is secured to the eyelet or end l2 of the spring ID. A second cable I6 is secured to a pivoted safety latch 11 secured on the hood.

As shown in Fig. 1, the points I I, 9 and I2 are in a straight line, due to the fact that the spring is in compression as a column or prop stick, and each end of the spring is pushing'in the direction of the arrows. Due to the pre-tensioning of the coils betweenthemselves, this spring in used as a prop-stick or column and with the shape as shown in Fig. 1, ofiers considerably more resistance in its normal position than after it has collapsed slightly.

The spring ID, that is a column of pretensioned coil wire with the ends extending ofi to the side in the same plan with the center of the spring, can be tailored to fit difierent counterweight problems. For instance, as "applied to the rear deck or cover of an automobile, it might be desirable tohave the spring even stronger during the top part of its stroke, due to the fact that the weight of the rear deck is on 'a'longer lever arm at that position. In, order to make the spring stronger at its top or extended position in relation to its collapsed position, it is necessary to pro-tension the spring more as it is wound, or to bring the center line of the spring closer to the center line of the spring coil.

v As the operator pulls the hood downward from the position shown in Fig, 1 to that shown'in Fig. '2; the hood does not tend to fall, but is counterwelghted all the way to the bottom of its Justv as the hood touches the end of its downward stroke, the spring shown in Fig. 2, pivots around the points of coincidence l2 and 9,due to the weight of the spring, and assumes the position shown in Fig. 3. In Fig.3, the

' its pressure applied position, Fig. 3, to the counter-weighting position, Fig. 2, the cable,

chain or band I3 is fixed to the leg of the spring at the point l4 and extends around the'eye of the spring, and this control member l3 extends to the inside of thecar where it isjconnected to a pull button on the dash. The movable points 8 and 9, which are spread apart, Fig. 5, come into approximate coincidence with the stationary point l2 in the closed position. By moving, the

point [2 slightly forward in relation to the'movable point 9 by making bracket 3 slightly longer, the cam action which results as the 'springialls downward causes the sprin tobe loaded an additional amount, which makes the spring help lift itself on the latter part of the return stroke and at the same time, holds the spring in its pressureapplied. position more firmly, due to the cross center position or the points 9, i2 and H, Fig.

3. The distance'betwee'n the points i l l' and i2 Fig. 2, is slightly greater than the distance be-r tween points II and 12 Fig. 3, which means that the spring has had'extra energy put into it during the change from the position in Fig. 2 to that shown in Fig. 3.

It is intended that the same mechanism be placed on each side of the hood, in which case the control cables can be interconnected; Or it is possible to apply one counterwei'ghting mechanism at the center of the hood. 1

tionary part of the automobile and the other arm pivotally connected to the other end of the link, said coil being adapted to bow when the hood is closed and acting to counterbalance the weight of the hood in its raised position and while being raised and lowered each arm being arranged at an angle so that the coiled section will flex in a curve always in the same direction when the hood is lowered from its raised position;

3. '-In combination with'an automobile having a hood, a hood lifter and support comprising a frame secured to the hood and having an inverted U-shaped member, a link pivotally secured at one end to the U-shaped member, and a coil spring having a lever-arm projecting at an angle from each end of the coil relative to the longitudinal axis of the coil and having onearm pivotally con- .nected to a stationary part of the automobile and the other arm pivotally connected to the other end of the link, said coil being adapted to bow .when the hood is closed and acting to counterbalance the weight of the hood in its raised position and while being raised and lowered each. arm being arranged at an angle so that the coiled section will flex in a curve always in the s'ame direction whenthe hood is lowered from its raised position.

4. .In combination with an automobile having a hood, a hood lifter and support comprising a frame secured to the hood. and having an inverted It is not necessary that the counterweight de vice shall be used in the exact combination shown since various modifications are possible.

1 within the scope of the appended claims; Also it is not necessary that all elements shallbeiused conjointly but they may be used in sub-combi- ;;;1

nations. v V, I claim as my, invention: 1 i V 1. In combination with a pair of relatively movable members, a counterbalance device comprising a spring'having a .pre-tensioned coiled section and a straightlever-armQsectionat each. end, each'straight lever-arm section extending atan angle relative to the longitudinal. axis of the spring, a movable lengthpivoted,to,. one of the members, onestraight section of the spring being pivoted to the other of themembersfanduthe other straight section to the link whereb upon movement of the members toward each otl'ier'the coiled section will be curved. axially as the ends of the straight sections approach each other and as the pivot for the spring pivotedto the other of the members is in approximate alignment with, the pivotoi the link to' one of the members, the link and spring moving as a unit, on. their. two

last-mentioned pivots to maintain the members in closed position under a tension when the meinfi bers are in contact with each other, said-straight sections being arranged angularlyso that the coiled section will flex into a curve alwaysin the same direction when the relatively movable mem bers are moved toward each other.

projecting at an angle from each end of the c'oil relative to th e longitudinal axis .of the coil and.

having one arm pivotally connected to a' sta U-shaped member, a link pivotally secured at one end to they U-shaped memberQand a coiled spring having a lever-arm projecting at an angle from each end of the coil relative to: the longitudinal axis of the coil and having one arm pivotally connected to a stationary part of theautomobile and the other arm pivotally connected to the other end of the link, said coil being adapted to bow when the hood is closed and acting to counterbalance the weight of the hood'in its raised position and while being raised and lowered, and said link and spring being shiftable as a unit around the pivot points when the hoodis down or closed to maintain the hood down under the spring pressure each arm being arranged at an angle so that the coiled section will flex in a curve always in the same direction when the hood is lowered from its raised position.

5. In combination withan automobile having a hood, a hood lifter and support comprising a spring having-a pre-tensioned coiled. section and at least one lever-arm straight section projecting at an angle from the coiled section relative to the longitudinal axis of the coiled section in a straight line position, said spring being pivotally connected at one end to a stationary part of the automobile and the coiled section flexing into a curved formation when the hood is lowered from a raised position and acting to counterbalance the hood in the raised position, and a link pivotally connected at one end to thehood and the other end to the spring whereby the link and spring may be moved as a unit to apply the force of the spring on the hood when the latter is in the closed position said arm being arranged at an angle so that the coiled section will flex in a curve always in the same direction when the hood is lowered from its raised position.

6. In combination with an automobile having a hood, a hood-lifter. and support comprisinga spiral coiled section under pre-tensionand the coils in contact with each other. in a' straight position of the spring, and a lever-arm integral with the coiled section projecting from each end of the spring and at an angle relative to the lo n gitudinal axis of the coil, said coiled section flex ing into a bowed position when th hood is actuated to counterbalance the hood in its open and intermediate positions, and means connected to one of the lever-arms and the hood for pivotally mounting the spring to permit the spring to swing when the hood is closed so that the spring will exert its force from a counterbalance pressure to a closed or hold down pressure, each arm being arranged at an angle so that the coiled section Will flex in a curve always in the same direction when the hood is lowered from its raised position.

7. In combination with an automobile having a hood, a hood-lifter and support comprising a spiral coiled section under pre-tension and the coils in contact with each other in a straight position of the spring, and a lever-arm integral with the coiled section projecting from each end of the spring and at an angle relative to the longitudinal axis of the coil, said coiled section flexing into a bowed position when the hood is actuated to counterbalance the hood in its open and intermediate positions, and means for pivotally mounting the spring to permit swinging the latter when the hood is closed so that the spring will exert its force from a counterbalance pressure to a closed or hold down pressure, said means including a pivoted link secured at one end to the hood and the other end to one end of the spring whereby said link and spring are shiftable as a unit, each arm being arranged at an angl so that the coiled section will flex in a curve always in the same direction when the hood is lowered from its raised position.

EDWIN E. FOSTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES The Art and Science Of Spring Making, page 44; Copyright 1937 by Barnes, Gibson, Raymond, Detroit, Michigan and Ann Arbor, Michigan. 

